Analysis for the clinical audiological characteristics in patients with auditory neuropathy

Objective To summarize the features of clinical manifestation and audiological characteristics in patients with auditory neuropathy(AN) in order to analyze the significance of audiometry detection in the diagnosis of AN,and to investigate its lesion site.Methods The audiological data of 52 AN patients were retrospective reviewed.The patients'clinical findings,pure tone threshold and the examination results by acoustic impedance audiometry,speech audiometry,auditory brainstem response(ABR),distortion product otoacoustic emission(DPOAE) and contralateral suppression were analyzed.Results In all the patients,the ratio of genders was 1:1.70(male:female).The patients'range was between 5 and 31 years,and averaged age was(16±7) years.All the patients complained of bilateral gradual hearing loss.The patients could not discriminate speech correctly,especially in noisy environment.Among 52 patients 28 patients(50.85%) complained of last or discontinuous tinnitus.4 patients developed evidence for a peripheral neuropathy.Most patients'audiograms showed a low frequency loss(93.3%,97/104).The patients'speech hearing was worse obviously than the pure tone hearing.ABR was absent or abnormal severely,but DPOAE in all the patients were normally recorded.Acoustic stapedius reflex was absent and the contralateral suppression effect of DPOAE was disappeared.Tympanogram curve was Acurve,and ipsilateral and contralateral acoustic stapedius reflexes were absent or present at some frequency,however,the acoustic reflex threshold was increased.Conclusion The clinical manifestation and systematic audiometry detection play an important role in the diagnosis of AN.The main lesion sites may be located in the afferent pathway of cochlear nerve and efferent pathway of cochlea